Takeda’s Phase III TIDES Trial Confirms Long-Term Efficacy and Safety of Qdenga Dengue Vaccine

Takeda has announced the completion of its 7-year, Phase III TIDES clinical trial (NCT02747927) evaluating the dengue vaccine, Qdenga. Along with an exploratory analysis of a booster dose, TIDES data confirm the favorable benefit and safety profile of Qdenga, as well as sustained protection following a two-dose regimen.¹

TIDES data demonstrate long-term effectiveness

Data from TIDES show:

• After 4.5 years, two doses of Qdenga demonstrated 61.2% vaccine efficacy (VE) in preventing virologically confirmed dengue.
• A booster dose given at 4.5 years increased efficacy modestly to 74.3% after two years.
• Qdenga demonstrated 84.1% VE against dengue-related hospitalizations at 4.5 years, rising to 90.6% after the booster.
• Protection was maintained across all four dengue virus serotypes for up to seven years.
• No new safety signals were identified following booster administration.

In a press release, Edson Moreira, MD, senior researcher at Oswaldo Cruz Foundation, Brazilian Ministry of Health, said: “We are seeing an unprecedented surge in dengue, with over 14 million cases reported across more than 100 countries in 2024 alone, largely driven by the impacts of climate change and inadequate urbanization. Brazil, consistently among the countries most impacted by dengue, has contributed to the record-breaking number of dengue cases and rise in severity and deaths. This surge highlights the urgent need for prevention methods like Qdenga. The inclusion of Qdenga in Brazil's public vaccination program has reduced symptomatic dengue cases and dengue-related hospitalizations.”

Approval and regulatory history

The Qdenga vaccine was first approved in Indonesia in 2022. Since, it has been authorized across 41 countries, and 18.6 million doses have been adminstered in 11 endemic countries as of September 2025.

However, Qdenga is not currently approved in the US. In July 2023, Takeda pulled back a Biologics License Application (BLA) for the then vaccine candidate following discussions with the FDA over aspects of data collection.²

TIDES study design

The TIDES study, which included participation from over 20,000 children and adolescents living in eight dengue endemic areas, was a double-blind, randomized, placebo-controlled trial.

• The trial evaluated two doses of Qdenga (TAK-003) for the prevention of laboratory-confirmed symptomatic dengue.
• Participants were randomized 2:1 to receive two 0.5 mL doses of TAK-003 or placebo at months 0 and 3.
• The trial included five parts, assessing efficacy, safety, durability, and booster response over a total follow-up of up to seven years.
• Conducted across eight dengue-endemic countries in Latin America and Asia, the study evaluated outcomes by serotype, baseline serostatus, and disease severity.
• TIDES is Takeda’s largest interventional clinical trial to date, with ongoing safety monitoring by an independent Data Monitoring Committee.

Ongoing evaluation

Takeda’s research of Qdenga is ongoing. To further understand the vaccine’s safety and impact, there is an Impact Study in the municipality of Dourados, Brazil in partnership with the Dourados Health Department, as well as the observational, post-authorization effectiveness study, DEN-401 (NCT06843226), of Qdenga in children and adolescents in Southeast Asia.

In the press release, Derek Wallace, MD, president of the Global Vaccine Business Unit at Takeda, added: “Qdenga is the most comprehensively studied dengue vaccine, with more than 60,000 participants globally in the clinical program, and these long-term data highlight the durability of its safety and efficacy profile, across diverse populations worldwide. We are proud to have worked hand-in-hand with the clinical trial participants, collaborators and investigators whose contributions have been integral to the success of the TIDES trial and played a role in helping us move closer to a dengue-free world.”

References

1. New Phase 3 Data Show Takeda’s Dengue Vaccine Delivers 7 Years of Sustained Protection Against Infection and Hospitalization. News release. Takeda. November 3, 2025. Accessed November 4, 2025. https://www.takeda.com/newsroom/newsreleases/2025/dengue-vaccine/

2. Takeda Announces Voluntary Withdrawal of U.S. Biologics License Application (BLA) for Dengue Vaccine Candidate TAK-003. News release. Takeda. July 11, 2023. Accessed November 4, 2025. https://www.takeda.com/newsroom/statements/2023/takeda-announces-voluntary-withdrawal-of-us-biologics-license-application-for-dengue-vaccine-candidate-tak-003/